Friday, November 11, 2011

Attic Ventilator Fans: The good, the bad, and the ugly!

It is common practice for homebuilders, roof specialists, and HVAC companies to tout the importance and benefits of attic ventilator fans. The argument, which seems to make a great deal of sense, is that by creating airflow in the attic (powered) the heat gains will drop dramatically, therefore reducing electric consumption for A/C units. Is this really the case? As with most things, there is not a clear “black and white” answer. The reality lies in the grey area that I have decided to study a bit.

Savannah Renovations conducts its business in and around Savannah, Georgia. We have a hot, humid climate to deal with most of the year. It is common during the summer for attic spaces to have temperatures in the 120 to 140 degree range and I have read that in some cases they can reach 160 degrees! The hot sun beats on the shingles conductively heating the roof deck, and then through radiant transfer, the air inside the attic space is heated to incredible temperatures. Most homes (especially newer ones) have the air handler which contains the cold coil that cools air and also removes humidity hence the need for the drip pan and drain on your home located in the attic as well…you can imagine what these temperatures do to your cooling bills.

The stage is set and many companies sell powered and solar ventilation fans touting that purchasing their equipment will save you thousands. The science seems sound and all us contractors rally behind it because it seems to be almost common sense. Pulling in air from the outside at 90 degrees and replacing the 130-degree air seems to be a no brainer.

Here are the real facts:

A study done by Danny S. Parker and John R. Sherwin from the Florida Solar Energy Center (FSEC) (1) Sheds some light on the actual benefits of attic ventilator fans. Their study of a single family home in Florida showed the fans (2 installed) reduced attic temperatures over 20 degrees and reduced air conditioning consumption by 6%. The downside of this is that the cost of the fans and installation made the return of investment very low taking almost 20 years to pay for itself.

In a more expansive study, John Tooley (Natural Florida Retrofit), and Bruce Davis from Alternative Energy Corporation's Applied Building Science Center, looked at the unintended consequences of the use of powered ventilators in attic spaces (2). Their study of eight homes found that the attic ventilators caused depressurization inside all the homes. This depressurization caused safety concerns. Specifically, they noted that a gas powered hot water heater was actually experiencing back draft issues causing normally vented gasses to be pulled into the home. In addition, there was the issue of loss air conditioned air; an average of 231 cubic foot of air per minute!

Does this mean that forced ventilation of your attic is a terrible idea? No, but care should be taken and hiring a qualified and knowledgeable professional to help choose the proper product and conduct the installation is important! This is a perfect place for me to mention Savannah Renovations as such a company.
In conclusion, there are benefits and consequences of installing attic ventilator fans. Here is a summary by bullet point of the most important:

Negative points to consider:

  • An electrically powered 1500cfm attic fan usues about 325 watts of electricity. In the Parker/Sherwin study their test fan used 284watts and generated 170watts of savings from reduced air conditioner use. Therefore, my opinion is that electrically powered fans are out of the question unless there is little or no insulation in the home. Solar ventilation fans use no electricity…nothing more to say about that.
  • Care must be taken in choosing the proper fan. Oversized (which is the norm) fans can cause depressurization, pulling air-conditioned air into the attic. They can also cause health and safety issues. Especially if you have gas powered appliances and utilities in your home. The Tooley/Davis study noted a story of a Colorado family who died from carbon monoxide poisoning when their attic fan caused their furnace to operate in back draft.

Positive points:

  • A properly installed attic fan should reduce the summer temperatures by about 20 degrees.
  • Attic fans reduce humidity in the attic area more than passive ventilation alone.
  • The above points result in a reduction in cooling bills (approximately 4-7% in my opinion), and increased longevity of air-conditioning units due to the decreased stress (less heat and humidity around the coil, air handler, ducting, etc.).
  • Solar powered units are the only way to go! They pull no parasitic energy from the grid, paying for themselves over the long term. Not only saving you money, but saving our environment as well.

Finally, I will reiterate a pervious point(s). Attic ventilator fans can be a positive addition to your homes energy system. However, hiring a knowledgeable professional to help with fan selection, location, and proper installation is critical to see actual savings and keep your family safe. I believe that Savannah Renovations is such a company. Give is a call or email to see how we can help you!

Robert F. Foy



Friday, May 20, 2011

LED lighting: Is it a cost effective, environmentally sound alternative?

Working with commercial customers over the years has given me the opportunity to take on projects that I would most likely not have had if I focused on residential alone. Recently, I have had the opportunity to complete a LED lighting upgrade that had enlightened me on the subject and my findings have been significant.

First, some background: This project took place at Goosefeathers Café in Savannah. The café has used rope lighting for years to accent and make their restaurant stand out, because it was off a very busy square downtown and close to other prominent and famous eateries. The lights are on 24 hours a day, seven says a week.

I brought up the idea of using LED lighting originally not because it would save electricity, but because the standard incandescent lights we were using were failing far too frequently. Rope lights (both LED and incandescent) run in sections of 18 to 42 inches and when there is a failure the entire section goes out. The incandescent usually start to loose sections in an 8 to 12 month period. Additionally, the café owner was purchasing the lights from one of the large box-type home improvement stores. This placed restrictions on lengths, and the lights were not repairable…once a section went out, the whole string had to be replaced!

Now that I have some real information and data to work with, I can say that LED lighting is definitely worth the investment! Real life experience and for comparative purposes, I am going to argue that the lights will last 1/3 of the lifecycle that the manufacturer suggests before this first sections start to fail.

Initial installation:
  • Installation costs of the incandescent lights are $1.87 per linear foot including all materials. Goosefeathers uses 300 linear foot for a total installation cost of $561.00
  • Savannah Renovations charged $3.26 per linear foot including all materials to install LED lighting. Total cost: $978.00

Operating costs…I used the power bill calculator at the Georgia Public Service Commission’s website ( ) to calculate the operating expenses of the lighting. Although these are not the exact rates and calculations used for a business of this type, the method of calculation is similar:

  • The incandescent lights we were using operated at 3watts per linear foot per hour. Again, at 300LF this totals 900 watts per hour used to operate the lights. Since the average month has 730 hours, the average power costs would be:
    • $93.24 per month during the summer
    • $83.83 per month during the winter
  • The new LED lighting purchased operates at .64watts per linear foot per hour; this totals 192 watts per hour to operate. Once more, using 730 hours per month (average), the power costs for LED rope light are:
    • $29.10 per month during the summer
    • $28.25 per month during the winter

Maintenance expenses: As previously stated, my real life experience tells me that (at least concerning incandescent) the lights will generally last 1/3 of what the manufacturer suggests before the first failures begin to occur. Since I do not have the actual experience with LED lighting, I will assume this lighting will react similarly. To get a good idea of average annual expense, I have chosen to use a 10-year period to assess maintenance costs. With this information and these assumptions, I feel the following hypothesis is accurate:

  • Most incandescent lighting manufacturers state a bulb life of 20 to 33k hours. My real life experience with the lights at the café show that in reality the period is more like six to ten thousand hours before the first sections start to fail. With the particular lights used here there are no repair options, so since the sections start to fail, the whole rope must be replaced. Rope sections average two to 48 foot in length. The average length used here is 18 linear foot. Repair generally costs a little more than initial install because the service is particular to a small section and the labor charges are higher.
  • The repair/replacement of sections is usually $2.25 per linear foot for the incandescent lighting including all materials.
  • Based on the realized historical lifespan, the entire lighting system will be replaced 8.85 times in a ten-year period.

  • The LED lights we purchased for the project at Goosefeathers Café state a 100k lifespan. If the LED lights follow the same lifespan as I have seen with incandescent lights, they should last approximately 35k hours.
  • Here is where the big difference in maintenance comes in: the LED lights purchased are repairable! This means, when a section goes out that section can be cut and replaced. There is no need to replace all the lights!
  • I estimate repair costs to be $3.50 per linear foot including all materials.
  • Based on my hypothesis, the entire lighting system will be replaced 2.5 times over a ten-year period.

Total of expenses over a ten-year period including initial installation, power usage, and maintenance costs:

INCANDECENT: $16,495.20 and 78,840kwh USED

LED: $7,039.00 and 16,819kwh USED


The results of my small study have surprised me. Incandescent lighting does have a significantly lower initial installation cost, but beyond that there is no comparison. LED lighting operates at such a low energy level and lasts so much longer there is little argument left. In this one case, the owners will save $9,456.20 in the next ten years compared to the previous ten! Not to mention the environmental impact…62,021kwh have been saved over this same period! That is 62,021,000 watt hours of electricity!!!

LED lighting is definitely cost effective and environmentally sound! Call or email Savannah Renovations today (912-675-5569) for a free estimate and consultation to see how we can help you save money and do your part to help protect the environment!

Thursday, March 24, 2011

Mortise Lock Repair

Mortise locks are common in homes from the Colonial, Federal, Victorian and Arts & Crafts periods. Dating from 1607 to the 1920’s (over three hundred years), these locks in various forms were widely used. There are many resources to replace these mechanisms when they fail; however, I have found that finding suitable parts that actually fit is difficult. To be honest, these mechanisms are fairly simple and repair can be done by just about anyone with a modest level of skill.

Removal: Removal of the mortise lock from the door is easy. Simply remove the two screws on the faceplate holding the mechanism in place.

Disassembly: The first step in the process is to find the machine screw that holds the cover plate in position and remove it. I am sure that there may be manufacturers that may have used a different (2, 3 or more screws) configuration, but I have never seen them differ from this:

Once the cover is removed, take note of the position of all the bolts, levers, and springs.

Take special care (and I speak from experience here!) to note the EXACT position of the retainer springs…and there will most likely be two of them. These springs are critical to smooth and proper operation.

This is also a good time to inspect the mechanism for damage and to note what repair actions should be taken. The most common reasons these mechanisms fail:
  • PAINT, PAINT, and did I mention PAINT? More often than not, at some point in history, someone painted over the mortise lock rendering it unusable. A simple cleaning of the parts in paint stripper and mineral spirits usually does the trick.
  • Broken springs. Suitable replacements can usually be found at a hardware store or online dealers abound.
Remove the springs first. In my example, there are three. Once the springs are removed the rest of the parts pretty much fall out so be careful. When you remove, the parts make sure to lay them out so you can remember how they go back.

Once the parts are cleaned, a liberal application of lubricant will help the unit operate smoothly. Do not use a spray (like WD-40) this stuff makes a mess and attracts dust/dirt. The best lubricants to use are Teflon, or graphite type lubricants. In this application, I would also accept the use a lithium based lubricant.

Reassembly is reverse of removal. Just be sure the leaf type retainer springs are placed exactly where they should be.

Test the operation of the cam, bolt, and latches before installing the mortise lock mechanism. You can use the door set and skeleton key to check that everything works.

Alternatively, if this seems a little difficult…Please give Savannah Renovations a call at 912-675-5569 and we will be right out to repair your mortise locks and have them working as good as new!

Wednesday, November 17, 2010

The Great Plumbing Myth!

Plumbing Myth: Using Baking Soda and Vinegar to Clear a Blocked Drain.

You can find it everywhere…even government (cities mostly) entities promote the use of baking soda and vinegar to clear a blocked drain. The common claim is that the mixture will somehow magically change grease and sludge in the drain into soap and glycerin…freeing the blockage and leaving your drain fresh and sparkly clean! Is it true? Could this grade school science project be a complete replacement for all plumbers and commercial drain cleaners? Let us embark on a scientific journey to find the truth behind this popular mixture!

The key ingredient in vinegar is acetic acid (ethanoic acid). The amount of acetic acid in table vinegar is usually 4 to 8% in common table vinegar (mildly acidic). Baking soda is essentially sodium bicarbonate, an amphoteric compound that is slightly alkaline. The mixing of the two creates a reaction (rush of bubbles) that we all remember when we were in school (the erupting paper mache volcano?).

The two chemicals (acetic acid and sodium bicarbonate) when mixed form a new chemical called carbonic acid…commonly found in carbonated beverages. Carbonic acid in this form however is very unstable and immediately breaks down and turns into carbon dioxide (the bubbles) and water. After all the carbon dioxide escapes all that is left is sodium acetate and water. Sodium acetate is commonly found in foods we eat…such as salt-and-vinegar potato chips.

My point in this lengthy explanation? None of the chemicals…before, during, or after the mixing of the baking soda and vinegar will help clear a clogged drain. None of the acids is strong enough to break down hair or soap. Heck, we eat this stuff every day! So what could it be?

Commonly during chemical reactions heat is created…maybe, it is the heat. Our reaction is known as a neutralization reaction and they are exothermic in general. However, there are a couple conflicting processes going on in this reaction that may actually cause the temperature to DROP!
·       Evaporation of the liquid occurs as the carbon dioxide escapes (remember the bubbles?). Evaporation absorbs heat.
·       Rapidly expanding carbon dioxide cools as it expands…this is known as Joule-Thomson cooling. A visualization of this can be seen with the common computer-cleaning product, canned air. Hold the nozzle open and see how cold it gets…freezing…very quickly!

Ok, so it is not the baking soda, the vinegar, the chemical process, any chemical, or the heat that will open a clogged drain. I am sorry to report that the science simply does not support the use of these household products as effective in clearing a clogged drain. If anything, it may clog it further as the remaining solids from the chemical reaction could form a grey sludge.

But wait!!!! There is still a great use for this in your kitchen…including your drains!

Baking Soda and white vinegar is great in sanitizing and getting rid of odors. It can help keep clear drains clean and keep them smelling fresh. In tests run at Virginia Polytechnic Institute and State University, Pairing the two killed virtually all Salmonella, Shigella, or E.Coli Bacteria on heavily contaminated food and surfaces when used in this fashion, making these two natural cooking ingredients more effective at killing these potentially lethal bacteria than chlorine bleach or any commercially available kitchen cleaner.

My suggestion…1/2 cup of baking soda, add ½ cup of vinegar in your drain (that is not currently clogged). Place the stopper on the drain if applicable. Wait 30 minutes or so and rinse down the drain with boiling water. Wait a few more minutes and flush completely with hot water from the tap to rinse down any remaining solids. This should help keep your drain clear and keep it smelling fresh.

Monday, November 15, 2010

Clogged Toilet?

Eventually, we all will have to deal with it…the dreaded clogged toilet. There are a lot of myths and facts on the subject. Drawing on my own experience and research, I will share some of these simple drain issues (I am sure you can barely contain your excitement!).

When dealing with a toilet that will not flush there are some toilet basics I am going to share to help you understand how toilet draining works. A standard toilet has a 2” drainpipe. This pipe is usually formed in a curve that is not unlike the curves on a road travelling through the mountains. This is called a trap, and the reason for this trap is to, well, trap water so that sewer gases do not come into the home. Good idea, right?

In any event, we have a 2” curvy pipe that leads into the sewer lines that are traditionally 3 or 4-inch lines. With that in mind, the vast majority of clogs in toilets are in the curved portion of the two-inch pipe in the toilet, because once the waste reaches the sewer line there is a lot more room…and less chance for a back up. The best way to clear this, in my experience is with more water. Take a large bucket and fill the toilet with water very quickly. Careful not to overflow the toilet though! This rapid addition of water creates agitation and the weight (water is very heavy!) will usually clear the blockage. If this does not work at first... Watch the water level in the bowl. If the water level slowly goes down, this is a good sign. Try adding more water (quickly) again.

If this method does not work, add water like before and pull out the old plunger. The added weight of the water helps the plunger’s efficiency. Again, be careful to not allow the water level in the bowl to rise too much…that could me messy!

One thing I always try to avoid, and never advise is the use of a metal “snake”. These are found at most hardware stores and usually made of a spring steel material. The reason you do not want to use a snake is that most toilets are made of glazed porcelain (or similar). The metal scratching against it can damage this glazing. Among other problems, it could make the surface rough in the trap…causing more clogs!

If these things do not work, I recommend contacting a professional. Savannah Renovations may be able to help! If you have a plumbing problem, give us a call at 912-675-5569 and if we cannot help, we can put you in touch with someone who can!

Thursday, September 16, 2010

Radiant barriers and radiant insulation: Real energy science or real scam?

Over the years, the subject of radiant barriers and radiant insulation has crossed my radar from time to time. Until now, I have not done any proper research or given it serious consideration. This past week however, I saw an ad in the local newspaper touting 75% savings and radiant insulation being more effective than twelve inches of insulation. So, I looked into the hype and science and I have come to the following conclusion:

Are radiant barriers and insulation real or just a fraud? Yes and No. I guess I should explain my position…

Radiant barriers and insulation work by reducing thermal transfer of heat from the roof itself and the attic floor. During the day, the shingles heat up and conductively heat up the supporting structure of the roof. These temperatures become very high and the heat from the roof deck and supporting structure radiates into the attic heating up the insulation on the ceiling of the home. Through this conductance and radiant heat, a greater load is placed on the air conditioning unit(s) to keep the home (structure) cool.  Basically, the radiant barrier reflects the heat back to the roof and reduces heat gain in the attic…more importantly, the heat gain to the insulation.

The science seems sound, but is it effective?

This is where the whole subject gets foggy. By definition, radiant barriers reflect RADIANT heat. With that information, I can immediately eliminate some installation procedures and barrier types. For example, some installers claim placing the radiant barrier directly below the shingles is acceptable and effective…Impossible! In order for a radiant barrier to work there ABSOLUTLY must be an AIRSPACE otherwise conduction takes over and immediately discounts any benefit of the radiant barrier. Studies done for the Department of Energy show the effectiveness of radiant barriers and insulation and two major installation procedures appear to be the most effective:

  • Installing the radiant barrier on the floor of the attic: The idea is that this method is effective in two ways. First, it reflects the heat from the roof deck upwards. Second, it reflects the interior energy downwards. Personally, I do not like this method because it creates hazards and in a study done by Oak Ridge National Laboratory the barrier looses its effectiveness as dust accumulates on the barrier. In addition, a study done by Texas A&M noted that reflective barriers work best when they directly face the radiant energy. The attic floor is not directly facing the roof deck so efficiency is lost. It creates hazards by covering the ceiling joists, potentially creating a hazard if one were to need to access the attic. If you cannot see the joist, you may just fall through the ceiling! Also, many homes have their utilities (electric, water, etc.) running through the attic. Reflective barriers contain metal…a conductor! Need I say more?
  • Installing the radiant barrier or insulation to the bottom of the roof deck: In my opinion, this is the most effective method that should yield the greatest efficiencies. The insulation directly faces the radiant source. Second, if attached to the bottom of the rafters there is an adequate space for the radiant heat to be reflected back towards the roof deck. In addition, this space will allow for the least accumulation of dust allowing the barrier/insulation to work at its greatest efficiency for the longest period. Finally, the placement should eliminate most, if not all contact with electrical lines reducing risk.

Without making this article a 400-page novel, I will summarize some of my points.

Yes, radiant barriers and insulation are effective. However, through the independent and government studies I have seen that I deem to be accurate any number over a 10% reduction in heating/cooling bills is difficult for me to swallow. The Department of Energy states “…radiant barriers can lower cooling costs between 5%–10% when used in a warm, sunny climate.”

Radiant barriers and insulation are one of the most cost effective ways to add efficiency. Generally, the materials and installation are less expensive than adding other insulation types.

Radiant insulation is better than a radiant barrier. This is due to the added insulation between two layers of barrier. The additional cost is minimal.

Studies also show that the major effects of radiant barriers and insulation are for reducing summer cooling bills in warm, sunny areas. The effect on winter heating bills is immeasurable in most cases and may even cause the heating bill to increase as the radiant heat from the roof deck is not warming the attic.

With all of this, my biggest gripe is with the manufacturers and installers that make huge energy savings claims. I have no idea why an installer would want to hurt his or her reputation or possibly even be sued from making these incredulous claims of energy savings.

Back to the newspaper ad…

“…cut your heating and cooling bills by 75% guaranteed.”

Really? Who is going to guarantee that? The installer? The manufacturer? I do not even know what to write about this. It is such an outlandish claim that I cannot imagine what is included with the installation to generate a 75% reduction in heating and cooling bills. Has such a reduction ever been documented?

“…delivers more energy savings than twelve inches of additional fiberglass insulation.”

I really have a hard time with this one. Again, from what I have read, this amount of additional fiberglass insulation should yield a much greater savings. I am not a scientist or a lawyer, but maybe there is something in the way this entire statement is worded that does not make it completely untrue.
So why do the manufacturers and installers feel the need to beef up their claims of such a great effect? My guess…this is needed to justify increasing the price of the product and the installation. I have no idea what companies that install this product charge their customers, but I have a feeling it may be more than it should be.

My bottom line…radiant insulation installed should run about one dollar per square foot installed. Depending on the particular structure and the potential difficulties, I can see no reason why it should ever be over $1.50 per square foot installed. Anything over this price almost completely nullifies your return on investment based on the research I have seen.

The studies and literature I based this article on:

Thursday, September 9, 2010

Important things to know when hiring any home service contractor

The term “Licensed and Insured” is, in most cases technically incorrect….or at least can be misleading. There are no special licensing requirements for many home service contractors in Georgia (painters, flooring installers, repair and maintenance contractors, etc. have no state licensing requirements beyond the essential business license). General contractors must be licensed by the state and must prove and carry liability insurance. If you call upon a licensed general contractor to complete a small remodeling, painting, etc. project be prepared for a hefty bill….and here is the real kick in the pants; He is simply going to call a sub-contractor and add his/her management fees!

Any repairperson or contractor you bring into your home or business should definitely have a business license and carry liability insurance. You should positively ask to see it because if you do not, you the homeowner are liable for any injuries or damage caused by the contractor and their employees! You are even liable for any sub-contractor’s employees and their injuries and actions! For example, you hire a contractor…say “Joe’s Handyman Service” to complete some drywall and painting in your home. Now let’s say Joe decides to hire “Mike’s Drywall Company” to prepare the walls for painting. Mike’s employee “Henry” is on the ladder sanding the drywall and he falls injuring his back and leg. Joe does not have insurance or a business license…neither does Mike. Guess who is responsible for all of Henry’s medical bills and time missed from work? YOU, the homeowner are 100% liable! Savannah Renovations, LLC carries a one-million dollar property liability policy and two-million in injury insurance brokered through Morris & Templeton Insurance.

You should always request a quote or estimate from your contractor. This is good for both the home/business owner and the company you are hiring. This works well for both parties to understand the pricing, payment schedule, and the exact expectations of the work to be completed. Verbal agreements can be acceptable if you have worked extensively with the contractor in the past; however, it is always best to have something in writing. This is often one of the most difficult jobs of being a contractor. I view it as Justitia (Lady Justice) holding the Scales of Justice. On one side of the scale is high quality (higher cost) and on the other is reduced-standard (lower cost) job in the estimating process is to find the correct balance. Let’s face it…you are not going to get a 1,600 square foot addition to your home for 500 bucks and a case of beer! I try my best to evaluate each customer and listen carefully to their words as they describe what is wanted and needed. I look at the quality of construction of the home or business to pick up clues as to the cost of construction and quality levels that currently exist. Armed with that information, I gather material pricing and estimate times, add overhead expenses and an estimate is born. I think all contractors do try to offer the best prices that we can…but in every case, there is a line that we simply cannot or will not cross. There is a point where money is lost…there is also a point where what is asked for could damage a companies reputation.

Once you have your estimate, beware of the bargain.
Most people like to get the most they can for the best price. Who would not? If you do have a bid that is much lower than the others are, and you feel that the contractor is reputable and offering an honest service…you should at least ask questions. It is possible that one of the contractors missed something important, or is quoting on different materials. These are important things to know when you are paying for any product or service.

Be careful of front-loaded payment schedules.
If any company needs more than 10% to begin your project this should be a huge red flag! The only reasons they would need the customer to pay up front is that the company is not solvent (which is bad enough), or worse…it could be a scam called “spiking the job” where a company takes a large amount of money upfront. Then by completing a small amount of work can avoid criminal charges….leaving you, the customer to deal with the civil issue of trying to get your money back. Being a business owner, I can certainly understand that contractors fear not being paid. They also would like some sort of “commitment” on the part of their customer. However, I also know that if excellent service and quality are offered…customer dead beats are usually not an issue. As a matter-of-fact in seven years, Savannah Renovations has never had a delinquent customer!

My last thought for today…

Know exactly what you want and expect before work begins.
To put is simply…
“While you are at it” can be the five most expensive words in the English language!